(GIS) Geographical Information System Essay Example | Topics and Well Written Essays - 2250 words

(GIS) geographic In stageion System - Essay ExampleThe hardware component of GIS is the central processing unit (CPU) or computer. It also includes a digitizer scanner whose function is to change info for usage those found in maps into digital form then s curiosity the converted selective information to the CPU. There are also a tape device whose function is to store programs or selective information on magnetic tap, and a disclose device which is employ to display data that has been processed. People as a component of GIS include end users and specialists whose function is to design the GIS for the end users. Methods refer to those procedures or techniques used data collection or processing. The practicable elements of GIS are data manipulation, data input and output, data retrieval and display, data psychoanalysis and modelling and data management. data input refers to incorporating data into the GIS whereas data output refers to removing data or information from the GIS. D ata analysis and modelling involves obtaining an understanding of relationships in the data collected and developing a model of the spatial phenomena. Data retrieval entails taking out data from a stored format for use whereas data display is the display off of the derived or primary data (Delaney and Niel 2006). In GIS, spatial data represent features that are stance-specific or geographic in nature. They include cell location like column and raw, and coordinates like longitudes and latitudes. On the another(prenominal) hand, attribute data deliberate a description of feature in a specific location and they can be in numbers or text strings. Unlike spatial data, attribute data can be measured in ratio, ordinal, interval and nominal ratios. According to Delaney and Niel (2006), topology creates an awareness of the meet for the GIS by developing a spatial data relationship. It links spatial and attribute data to give information on what surrounds a feature. When representing ro und-the-clock and discrete geographic features, vector data structure uses points, polygons and lines whereas raster data structure make tessellation on the representation surface through a repeated use of a square cell or a pixel. However, raster data structures are better at representing a continuous surface. Vector data structure support typology better and are more accurate in representing geographic features compared to raster data structure. Generally, raster data structure requires has a lower processing power requirement compared to vector data structure. On-screen digitising, converting, importing and geo-locating/geo-rectification are the four common methods of incorporating digital data into a GIS. On-screen digitising involves locating features from digital sources for example orbiter or scanned images using a computer mouse. Attribute data is entered through computer keyboard. Geo-locating is used to input non-geographic/non-georeferenced data into GIS because it conve rts spatial data into geographic data. Converting is done if GIS data is in a format that cannot be used by certain software. Importing involves obtaining data from other sources like geo-coded textual data, satellite images or digital aerial photographs into the GIS. There exist differences in cost, effort, time, and editing requirements between on-screen digitising, converting, importing and geo-locating/geo-rectification, examine and vectorisation, table digitizing and keyboard entry as data input methods. Both importing and converting are fast, cheaper, need little efforts and have less editing requireme